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package tutorials;
import smile.*;
// Tutorial1 creates a simple network with three nodes,
// then writes its content as XDSL file to disk.
public class Tutorial1 {
public static void run() {
System.out.println("Starting Tutorial1...");
Network net = new Network();
int e = createCptNode(net,
"Economy", "State of the economy",
new String[] {"Up","Flat","Down"},
160, 40);
int s = createCptNode(net,
"Success", "Success of the venture",
new String[] {"Success","Failure"},
60, 40);
int f = createCptNode(net,
"Forecast", "Expert forecast",
new String[] {"Good","Moderate","Poor"},
110, 140);
net.addArc(e, s);
net.addArc(s, f);
// we can also use node identifiers when creating arcs
net.addArc("Economy", "Forecast");
double[] economyDef = {
0.2, // P(Economy=U)
0.7, // P(Economy=F)
0.1 // P(Economy=D)
};
net.setNodeDefinition(e, economyDef);
double[] successDef = new double[] {
0.3, // P(Success=S|Economy=U)
0.7, // P(Success=F|Economy=U)
0.2, // P(Success=S|Economy=F)
0.8, // P(Success=F|Economy=F)
0.1, // P(Success=S|Economy=D)
0.9 // P(Success=F|Economy=D)
};
net.setNodeDefinition(s, successDef);
double[] forecastDef = new double[] {
0.70, // P(Forecast=G|Success=S,Economy=U)
0.29, // P(Forecast=M|Success=S,Economy=U)
0.01, // P(Forecast=P|Success=S,Economy=U)
0.65, // P(Forecast=G|Success=S,Economy=F)
0.30, // P(Forecast=M|Success=S,Economy=F)
0.05, // P(Forecast=P|Success=S,Economy=F)
0.60, // P(Forecast=G|Success=S,Economy=D)
0.30, // P(Forecast=M|Success=S,Economy=D)
0.10, // P(Forecast=P|Success=S,Economy=D)
0.15, // P(Forecast=G|Success=F,Economy=U)
0.30, // P(Forecast=M|Success=F,Economy=U)
0.55, // P(Forecast=P|Success=F,Economy=U)
0.10, // P(Forecast=G|Success=F,Economy=F)
0.30, // P(Forecast=M|Success=F,Economy=F)
0.60, // P(Forecast=P|Success=F,Economy=F)
0.05, // P(Forecast=G|Success=F,Economy=D)
0.25, // P(Forecast=G|Success=F,Economy=D)
0.70 // P(Forecast=G|Success=F,Economy=D)
};
net.setNodeDefinition(f, forecastDef);
net.writeFile("tutorial1.xdsl");
System.out.println(
"Tutorial1 complete: Network written to tutorial1.xdsl");
}
private static int createCptNode(
Network net, String id, String name,
String[] outcomes, int xPos, int yPos) {
int handle = net.addNode(Network.NodeType.CPT, id);
net.setNodeName(handle, name);
net.setNodePosition(handle, xPos, yPos, 85, 55);
int initialOutcomeCount = net.getOutcomeCount(handle);
for (int i = 0; i < initialOutcomeCount; i ++) {
net.setOutcomeId(handle, i, outcomes[i]);
}
for (int i = initialOutcomeCount; i < outcomes.length; i ++) {
net.addOutcome(handle, outcomes[i]);
}
return handle;
}
}